Refrigerating apparatus



Dec. 6, 1 938. E. F. SCHWELLER 2,139,521

REFRIGERATING APPARATUS Filed Dec. 27, 1933 4 Sheets-Sheet 2 A v TOR y v M 4 ATTORNEYS Dec. 6, 1938. p E sc w L 2,139,521

REFRIGERATING APPARATUS Filed Dec. 2'7, 1933 4 Sheets-Sheet 3 a Y EZTZR Dec. 6, 1938.

E. F. SCHWELLER REFRIGERATING APPARATUS Filed Dec. 27, 1933 4 Sheets-Sheet 4 lg BY lNl/gENTOR v 5 Mw/fla) ATTORNEYS Eli Patented n... s, 1938 UNITED STATES PATENT OFFICE BEFBIGEBATING APPARATUS Edmund F. Schweller, Dayton, Ohio, assignor to General Motors Corporation, Dayton, Ohio, a corporation of Delaware Application December 27, 1933, Serial No. 204,153

8Claima.

Heretofore, as far as I am aware, no refrigerator has ever been successfully manufactured wherein the completely assembled outer wall construction has, as a unitary structure, been provided with a coating of porcelain in the same operation. Obviously, because of the saving in manufacturing costs, such a construction has many times been attempted but as far as I am aware all such attempts have failed. These unsuccessful attempts have been due to many reasons. For instance, during the process of applying a coating of porcelain to metal, it is necessary to subject the metal to be coated to a temperature of about 1550 F. At such a temperature the sheets of metal lose a considerable portion of their strength and stiffness and are subject to warping. It has also been found that dur-:

It is the object of my invention to provide a completely assembled refrigerator wall structure to which porcelain can be applied without being subject to prior objections heretofore inherent in prior constructions. This object is accomplished as hereinafter more clearly pointed out by improving the construction of the refrigerant wall to permit expansion and contraction thereof within the elastic limitsof the metal and by improved technique in the handling and supporting of the wall structure during the process of applying the enamel. I

A further object is to provide an improved method of applying the porcelain coating and of handling the wall structure during that process.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanye invention wil be apparent from the following deing drawings wherein a prefered form of the present embodiment is clearly shown.

In the drawings:

Fig. 1 is a front vertical sectional view of a refrigerator cabinet embodying my invention;

Fig. 2 is a sectional view along the line 22 (3 Fig. 3 is a sectional view along the line 3-3 of Fig, 2;

. Fig. 4 is a fragmentary enlarged view of an upper corner of the cabinet showing. reinforcing means at one of the corners of the doorv opening;

Fig. 51s an enlarged fragmentary vertical sectional view of the lower rear portion of the cabinet;

Fig. 6 is an enlarged fragmentary sectional view of a lock seam shown at the rear of Fig. 3;

Fig. 7 is a view illustrating the method of supporting the refrigerator cabinet during the process of burning the porcelain on to the outer walls thereof; and

Fig. 8 is a top view taken along the lined-8 of t Fig. 7.

Referring to the drawings and more particularlyto Fig. 1, there is shown a frameless porcelain coatedsheet metal refrigerator cabinet 20 having an outer sheet metal shell, including the outer walls 2|, formed of a sheet extending continuously around the front, side, and the edge portions 22 and 23 of the rear walls and connected to a rear sheet 24 by lock seams 25 and 28 as illustrated in Fig. 6 to form a vertical tubular member generally rectangular in cross section having a rectangular openingin the frontwall of the cabinet and provided with a flanged edge 21 to form an opening for the cabinet door. Within the interior of the outer shell, at the corners 'of this flanged door opening, as shown in Fig. 4, there are welded angle-shaped flanged reinforcing members for preventing deformation during the burning of the porcelain. The vertical tubular member which provides the main supporting structure and generally serves as the frame of the cabinet, is provided with an inturned' flange 2d at its bottom edge which is preferably made particularly stiff by folding and doubling over the sheet metal to provide the flange 28 with two thicknesses of sheet metal. Supported by this flange is an intermedlatesheet metal partition or wall 30 which divides the machine or compressor compartment 3| from the food storage compartment 32. This intermediate partition is horizontal and is not supported directly from the adjawhich rest upon the inturned flange 28 at the bottom of the outer walls of the cabinet.

The machine compartment 3i is provided with a flanged ventilating opening 96 (see Fig. 5) in its shell.

' At the topof the outer walls or outer shell thereis provided a second transverse partition .5 which has its center portion extending upwardly and provided with a central aperture 45.,

This top transverse partition 44 .is provided with channel-shaped gussets 41, better shown in Flg.-

8, which extend diagonally across the outer corners of this sheet metal partition. These gussets are provided with an upstanding boss 48 which contains an aperture 49 for holding the cabinet in proper position when in the crate pro- 5 vided for Shipping the cabinet.

At this point in the assembly, the outer walls are ready to be provided with their porcelain coating. An inspection of the cabinet at this stage in the assembly will disclose that the outer sheet metal walls extend from top to bottom free of any connection with any other members except at the extreme top, and bottom, and around the flanged ventilating opening 96 at the back of the cabinet so that thermal expansion of the metal during the burning operation may be accommodated by freely permitting the intermediate portions of the outer walls to bend and to bow within the elastic limit of the sheet metal so as to prevent the concentration of strains and excessive deformations at certain points in the structure and also to prevent chipping of the porcelain. However, the transverse partition 44 at the top of the cabinet prevents any misalignment and preserves the required dimensions at the top of the cabinet, whilethe flange 28 at the bottom of the cabinet preserves the alignment and the straightness of the lower portion of the wall, and the reinforcing angle members 95 strengthen the weak points at the corners of the flanged door opening 21.

By this construction, the spot welds or other fastening means ordinarily required at intermediate portions of the front and side walls of a refrigerator of this type are thus eliminated. This also eliminates, the hand work required of metal finishers in dressing such spot welds and in this way the manufacturing costs of the cabinet are materially reduced.

In order to apply the porcelain, the outer shell in this stage of assembly is provided with a heavy rigid supporting spider frame 10 (see Figs. 7 and 8) which is placed within the interior of the shell and which has four arms, one extending into each of the comers of the cabinet, each being provided with upturned knife edge extremities II which engage the underside of the transverse partition 44 immediately beneath one edge of each of the gusset members 41. Adjacent the central aperture 45 the four arms are each provided with an upper projecting pin 12 having a conical point which is in engagement with a central point upon the under side of the transverse partition 44 in order to preserve the shape of this partition during the burning of the porcelain. The central aperture 45 receives the hook l3 and also facilitates the cleaning of the outer shell by permitting the escape of air and air bubbles when in the cleaning baths. The spider I0 is supported by a vertical hook 13 which extends upwardly through the aperture 45 and hooks on to one of the hooks 14 extending downwardly from the conveying means 15. By suspending the shell in this way, the outer walls are supported in substantially a direct tension, thus avoiding any strains which would be likely to cause sagging or distortion of the outer walls. The upper transverse partition 44 is properly supported by the projections H and 12 so as to prevent any distortion or sagging while it is maintained at furnace temperature.

After being placed upon this conveying means,

' the cabinet is carried through cleaning baths and then is provided with a coating of porcelain material or slip which is made up of frit, pigment,

; and clay. After this coating has been applied,

the shell is then carried by the conveyor means 15 into the furnace I6, maintained at a tempera ture of between 1500 and 1600 F., where the shell is kept a suflicient length of time in order to insure proper burning of the porcelain coating. Ordinarily at least two, and usually three, coats are provided consisting of a ground coat, usually black, and two white finishing coats.

After this operation is completed, the central aperture 45, is closed by a rubber grommet 45 and sealed by asphalt around the edges of the grommet as well as around the inside edges of the transverse partition 44. The intermediate partition 30 is likewise sealed around its edge portion by an asphalt seal 52. 'In this way, the interior of the outer shell is sealed against the entrance of external air and moisture. Bythus sealing the outer shell against the entrance of external air and moisture and by providing a flange type door with an air seal extending around the flange, air is prevented from entering the insulation space from the outside. This is particularly important since the warm external air would pass through the outer walls into the insulation space and would be cooled by the cold walls of the inner liner, thus probably reducing its temperature below the dew point and causing the collection of moisture within the insulation space. This, of course, would tend to reduce the effectiveness of the insulation. However, with applicants improved construction leakage, if any, must take place from the food storage compartment into the insulation space. Such leakage, however, is not a serious problem since the air in this way goes from a colder temperature into a warmer temperature which reduces the relative humidityof such leakage and thus no moisture will condense within the insulation space.

The ordinary assembly of the cabinet is then re-- to the angle iron frame'in order. to make the frame into a rigid unitary structure. Extending from one side of the angle iron frame to the other is a channelshaped bar 38 which supports the front edge of the compressor-condenser assembly, designated in general by the reference character 39. Upon the bottom of the cabinet there is provided four porcelain surfaced legs 40 which are separated from the flange 28 of the outer sheet metal walls by a felt pad; These legs 40 are fastened to the cabinet by nut and bolt means 4| which pass through the angle iron frame and the flanges 34 and 28 of the intermediate wall supporting means and the outer walls of the cabinet, as well as through the flange 42 provided at the top of the leg 40.

The cabinet is provided with a removable top cover 50 similarly provided with a porcelain coating and having an ornamental shape which is provided with a rubber gasket 5| extending around its-flange in order to provide a. tight flt with the outer walls or outer shell of the cabinet.

As mentioned before, the front wall portion of the outer sheet metal walls or outer shell is provided with anaperture for the door having a opening inside of the flanged edge is a rectangular door jamb frame 53 preferably of wood or some other material having low heat conductivity. Within the door opening and iastened to the door jamb frame by the wood screws 54 is a rectangular frame 55 of some suitable material having low heat conductivity,such as wood, which serves as the door molding. Fastened to the rear of this door molding by the wood screws 56 is a rectangular box-shaped sheet metal inner liner 5! which forms the inner walls of the cabinet surrounding the food compartment 32., .This inner liner, as, is customary, is preferably coated withstainless white porcelain.

At the sides of the inner liner bl there is formeda plurality of projections 58 which support the shelves :59 within the food compartment 32.

The door opening of the food compartment M is closed by an insulated door 86 supported upon hinges and provided with a latch bill. This door porcelain, which is also fastened to the frame ti.

A rubber sealing strip tit extends around the edges of the door between the edges of the inner and outer sheet metal members to seal the door. Eetween the inner and outer sheet metal members t2 and $3 is the insulating means tit in the form oi an insulating panel made up of a plurality of sheets ht of some suitable material, at least some of which have a heat reflecting surface, such as aluminum or zinc foil, which sheets are held in spaced relation with air spaces in between by a plurality of rectangular wood irames db which are stacked together to form a panel structure which is provided with an outer moisture excluding envelope at of some suitable material, such as asphalt paper. Similar insulating panel structures, designated by the reference character it, are provided between the inner sheet metal lining Sal and the transverse partitions 3t and it and the outer walls ii of the outer shell.

Within the food compartment 32 is a refrigerant evaporating means til containing refrigerated shelves ti for supporting a plurality of ice trays 82. This refrigerant evaporating means is supported by the top wall of the inner liner ti and cools the interior of the food compartment 32 as well as freezes ice cubes in the ice trays 82. The refrigerant evaporating means t0 is connected by refrigerant conduit means ti which extend througha groove or passage 84 in the front wall of the cabinet above the door molding and thence rearwardly beneath the removable top ornamental cover to to the refrigerant compressing and condensing means 39.

This refrigerant condensing means 39 comprises a vertical plate-like condenser 85 formed of two sheets of metal whichv are welded together at their edges and at certain points between they edges to form a thin container containing narrow passages extending from the top to the bottom of the condenser. The condenser is provided with a supply header 86 at the top which is connected by the refrigerant passages between the sheets to a distributing header 8! which in turn is connected by refrigerantpassages between the sheets to a receiving header '8 at the bottom of the condenser. The condenser is supported by the flanges 89 which are bent first rearwardly and then forwardly and fastened to the rear sheet metal portion 24 of the outer shell so as to sup-- port the condenser parallel to but spaced from the rear wall of 'the cabinet and to prevent the condenser from being placed tightly against a i port the motor-compressor unit 92 as well as a switch means 93.

By this structure, I have provided a porcelain refrigerator which is excellent in appearance and operation and easy and economical to manuiaoture.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted. all coming within the scope of the-claims which follow.

What is claimed is as follows:

1. A cabinet including vertical outer sheet metal walls extending around a space to be enclosed, d sheet metal walls being provided with a door opening therein having its center point displaced in a vertical direction from the mid point between the upper and lower extremities of the outers, transverse sheet metal partltion walls within said outer sheet metal walls spaced substantially equal distance in opposite directions from the edges of said door opening to provide an enclosed space between the sheet metal partition walls and a second space within said outer sheet metal walls adjacent one of. said partition walls and the first mentioned enclosed space, said outer sheet metal walls having an open portion adjacent said second space,

said partition wall adjacent said second space being provided with its own individual supporting means upon sides other than the side having the open portion se 1 to from said outer sheet metal walls but extending through said second space to and being fastened only to the extremity of said outer sheet metal walls adjacent said second space.

2. A cabinet lnclu vertical outer sheet metal walls extending around the cabinet, said outer sheet metal walls having plane wall portions, one of said plane wall portions being open adjacent one of its extremities, a partition wall within the coes of said outer sheet metal wallsporting means extending to and being fastened only to the extremities of said vertical outer sheet metal walls adjacent said open portion, and a solidified sealing substance extending around said partition wall providing a hermetic seal between all the edges of said partition wall and adjacent portions of said outer sheet metal walls.

3. A refrigerator cabinet comprising an inner liner forming a refrigerating compartment within said cabinet and having an access opening, insulating material surrounding said inner liner, and means forming asupporting structure for the liner and insulating material and forming as well the outer finish walls for the cabinet, said -means comprising a substantially tubular sheet til metal structure having an opening in one sidei thereof adapted to register with said compartment access opening, said tubular sheet metal structure having wall portions extending from the refrigerating compartment to form a second compartment, a partition wall within the extending portions of said tubular sheet metal structure dividing said second compartment from the inner liner and insulation for the refrigerating compartment, said partition wall having sheet metal supporting means independent of said tubular sheet metal structure but extending along the inside of said tubular sheet metal structure and being fastened only to the extremities of the extending portions of said tubular sheet metal structure.

4. A refrigerator cabinet including vertical sheet metal walls extending around the cabinet, said sheet metal walls being provided with an inturned flange at the lower edge thereof, a partition wall above said inturned flange extending between the vertical sheet metal walls, said partition wall having means extending downwardly and resting upon said inturned flange for supporting said partition wall, legs beneath said flange, and fastening means extending through the flange and fastening the legs and the downwardly extending means to the flange.

5. A refrigerator cabinet comprising an inner liner forming a refrigerating compartment within said cabinet and having an access opening, insulating material surrounding said inner liner, and means forming a supporting structure for the liner and insulating material and forming a well the outer finish walls for the cabinet, said means comprising a four-sided substantially tubular sheet metal structure having an opening in one side adapted to register with said compartment access opening, said tubular sheet metal structure having wall portions upon at least two sides extending from the refrigerating compartment to form a second compartment, a partition wall within said tubular sheet metal structure dividing said second compartment from the inner liner and insulation for the refrigerating compartment, said partition wall having sheet metal supporting means extending along the inside of said tubular metal structure independently of the tubular metal structure to the extremities of said wall portion extending from the refrigerating compartment, said supporting means being fastened only to the extremity of said wall portions extending from the refrigerating compartment, said second compartment having an opening upon one of the four sides of the tubular sheet metal structure.

6. A refrigerator cabinet cpmprising, an inner liner forming a refrigerating compartment within said cabinet and having an access opening, insulating material surrounding said inner liner, and means forming a supporting structure for the liner and insulating material and forming as well the outer finish walls for the cabinet, said means comprising a substantially tubular sheet metal structure having an opening in one side thereof adapted to register with said compartment access opening and including a one-piece sheet of material formed into an element extending continuously across the side of the cabinet having the access opening therein and continuously along the two adjacent sides of the cabinet and having its ends connected at the side of the cabinet opposite the access opening, a partition wall extending transversely within the tubular sheet metal structure adjacent the insulating material for one wall of the inner liner, said partition wall being spaced from one of the extremities of the one-piece sheet of material to provide a machine compartment upon the face opposite the insulating material, said partition wall being supported by means extending to and being fastened to the extremities of the oneplece sheet of material, said means extending serving as the sole structural connection between the partition wall and the one-piece sheet of material upon three sides of the cabinet.

7. A refrigerator cabinet comprising, an inner liner forming a refrigerating compartment Within said cabinet and having an access opening, insulating material surrounding said inner liner, and means forming a supporting structure for the liner and insulating material and forming as well the outer finish walls for the cabinet, said means comprising a substantially tubular sheet metal structure having an opening in one side thereof adapted to register with said compartment access opening and including a one-piece sheet of material formed into an element extending continuously across the side of the cabinet having the access opening therein and continuously along the two adjacent sides of the cabinet and having its ends connected at the side of the cabinet opposite the access opening, a partition wall extending transversely within the tubular sheet metal structure adjacent the insulating material for one wall of the inner liner, said partition wall being spaced from one of the extremities of the one-piece sheet of material to provide a machine compartment upon the face opposite the insulating material, said partition wall being supported by means extend-.

ing to and being fastened to the extremities of the one-piece sheet ofmaterial, said means extending serving as the sole structural connection between the partition wall and the onepiece sheet of material upon three sides of the cabinet, said one-piece sheet of material being provided with a continuous outer coating of porcelain.

8. A refrigerator cabinet comprising an inner liner forming a refrigerating compartment within said cabinet and having an access opening, insulating material surrounding said inner liner, and means forming a supporting structure for the liner and insulating material and forming as well the outer finish walls for the cabinet, said means comprising a substantially tubular sheet metal structure having an opening in one side thereof adapted to register with said compartment access opening, said tubular sheet metal structure having wall portions extending from the refrigerating compartment to form a second compartment, a partition wall within the extending portions of said tubular sheet metal structure dividing said second compartment from the inner liner and insulation for the refrigerating 

